
Screenshots

Watch trailer on Steam ↗Cthulhu Mythos ADV The Isle Of Ubohoth
Gotcha Gotcha Games · Published by Gotcha Gotcha Games · Official site ↗
Content notice: *The game contains some gory scenes.
Positive — 89% positive (37 reviews)
Last updated 28 Sept 2026
A horror dice roll adventure inspired by the Cthulhu Mythos. Much like in a tabletop RPG, "abilities," "luck," and "dice rolls" influence the story's progression. The protagonist is cursed on an island in the Seto Inland Sea. Investigate the island, uncover the mysteries, and break the curse!
£8.99
£14.99Lowest price we've ever recorded
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Price history
Adventure, Indie, RPG · 2024 · More £5 - £15 games
Embark on a chilling adventure set on the haunted Isle of Ubohoth. With Gotcha Gotcha Games guiding your path, navigate through mystery and dread using luck and skill to break an ancient curse.
About this game
Just Updated
We’ve added new gameplay features and convenient functions in this Complete Edition Update!
・Cryptic Notes

・Enhanced Visual Effects

The features below are also added,
experience an enhanced and more engaging version of "The Isle of Ubohoth"—we hope you enjoy it!
・Harasho’s Journal
・Puzzles
・Success Rate Control
・Various Other Improvements
Additional Feature Update!
The following functions have been added in response to many requests.
▼ Skip Function(Function changed from fast forward to skip)

▼ Ending List
About the Game
On a mysterious island in the Seto Inland Sea, an urban legend tells that completing the "88 Temples Pilgrimage" will summon Kukai, who will grant your wish. Our protagonist, visiting this island, is suddenly cursed by an unknown entity, putting their life in jeopardy. Can they prevent the resurrection of an ancient evil god sealed on the island and break the curse?
・Player Stats and Appearance Customization
Answer questions to shape your protagonist’s stats.
Enjoy thrilling dice rolls with challenging stats, and for an added layer of immersion, you can even replace the protagonist’s image.
・Dice Roll Choices

In critical moments, the outcome of choices is determined by dice rolls. The success rate depends on the abilities of the protagonist and their companions. Sometimes, you will face scenes where you must succeed within a time limit!
・Explore the Map

Search for clues to break the curse as you travel around the island.
Keep an eye on your hunger level—it decreases with each move and can impact your dice rolls.
・Solve Mysteries


Unravel cryptic notes and solve puzzles to uncover the island’s hidden truths.
Hatsumi Amasawa CV:Mayu Mineda
A friend of the protagonist and a university student.
Cheerful and friendly with everyone, likely due to her good upbringing.
Has a fondness for occult content like horror and urban legends.

Reiji Kaga CV:Haruki Ishiya
A friend of the protagonist and a university student.
Although he excels academically, he postpones job hunting to focus on his hobbies and part-time jobs.
While his interests in horse racing and pachinko haven't yielded great results, his excellent memory and insight make him unbeatable at mahjong.

Hotaru Natsunagi CV:Yuki Tanaka
A girl living on the island.
Due to her frail health, she's never left the island and yearns for city life.
After an unexpected encounter with the protagonist, the wheel of fate for both her and the island begins to turn.

Yukitsune Saeki CV:Yuya Hirose
A young man living on the island.
Possesses mysterious powers and spends his days helping others.
Claims the protagonist is his "destined person," but his true intentions remain unclear.

Keiyū Natsunagi CV:Hidenobu Kiuchi
Hotaru’s father.

How to Change the Protagonist's Image
Steps to Update Player Image
1. Open the game's page on Steam.
2. Ensure the game is installed.
3. Click the gear icon on the right side of the screen and select "Manage," then "Browse Local Files." This will open the folder containing the game's files.
4. Place the images in the Jukashima_Data/StreamingAssets/player folder. Ensure the images adhere to the specified size and file naming conventions to be displayed correctly in the game.

Image Specifications
Size: 1920x1080 pixels
File Format: PNG with a transparent background
Number of Images: 11 (for different facial expressions)
File Names:
・tsujo.png
・odoroki.png
・kyouki.png
・hohoemi.png
・egao.png
・aseri.png
・hensou.png
・hensou_aseri.png
・ikari.png
・kanashimi.png
・fushin.png
Note: "hensou" is displayed during undercover investigations. Enjoy preparing your favorite disguise illustrations.
For the Mac version, right-click on Jukashima.app and select "Show Package Contents." Then, place the images in Contents/Resources/Data/StreamingAssets/player.
Japanese, English
System Requirements
Will my PC run this? →Minimum
- OS *: Windows 7 / 8 / 8.1 / 10 / 11
- Processor: Intel Core2 Duo or better
- Memory: 4 GB RAM
- Graphics: Compatible OpenGL
- Storage: 500 MB available space
Recommended
- OS *: Windows 7 / 8 / 8.1 / 10 / 11
- Processor: Intel Core2 Duo or better
- Memory: 4 GB RAM
- Graphics: Intel HD 615Graphics or better
- Storage: 500 MB available space
Supported Languages
Latest news
Patch NotesOfficial
Korean Language Update : “Cthulhu Mythos ADV Lunatic Whispers”
Korean Language Update for the First Title in the Series: “Cthulhu Mythos ADV Lunatic Whispers”We hope even more players will enjoy this unique “solo-play TRPG experience.”Read full article on Community Announcements (Gotcha Gotcha Games)AnnouncementsOfficial
"Cafe DReAMLAND + Cthulhu Mythos ADV Series Special Bundle" is now on sale!
The Cthulhu Mythos ADV Series titles “Cthulhu Mythos ADV Lunatic Whispers” and “Cthulhu Mythos ADV The Isle Of Ubohoth”, along with the Cthulhu-mythos-inspired adventure “Cafe DReAMLAND”, are now available together in one bundle!It’s a perfect opportunity to grab the titles you haven’t purchased yet—at a special discounted price.Cool off this summer with the cosmic horrors of the Cthulhu Mythos!👉 \Read full article on Community Announcements (Gotcha Gotcha Games)Patch NotesOfficial
Bug Fixes – April 10, 2025
We have fixed the following issues: ・On the map screen, if the player gives up on deciphering the ""mysterious letter,"" the spot detail screen may not display correctly. ・Opening the menu while reading a ""note"" can sometimes cause unintended behavior. ・On DAY 4, performing certain actions may cause the background image to not display correctly. We kindly ask that you update your game data to implement the necessary fixes. We truly appreciate your understanding and apologize for any inconvenience this may have caused.Read full article on Community Announcements (Gotcha Gotcha Games)Patch NotesOfficial
Bug Fixes – April 1, 2025
We have fixed the following issues: ・The Bad End - "Mission Accomplished" occasionally failed to trigger, even when the necessary conditions were fulfilled. ・In cut-in scenes, the default protagonist image appeared instead of the designated illustration. ・The DAY 7 puzzle did not progress as intended. ・When adjusting the dice roll success rate manually, the display on the button did not consistently reflect the actual success rate. We kindly ask that you update your game data to implement the necessary fixes. We truly appreciate your understanding and apologize for any inconvenience this may have caused.Read full article on Community Announcements (Gotcha Gotcha Games)Patch NotesOfficial
Complete Edition Update! (2024/12/26)
We’ve rolled out the Complete Edition Update, packed with new gameplay features and convenient functions! Whether you're a first-time player or someone who's already explored the game, the enhanced "Cthulhu Mythos ADV The Isle Of Ubohoth" experience offers even more thrills. Don’t miss out—dive back in and enjoy! New Features ▼ Cryptic Notes Hidden across the island, cryptic notes now challenge your wits. Each one is a riddle—put your creativity and problem-solving skills to the test! ▼ Harasho’s Journal Decode the cryptic notes to unlock entries from Harasho’s journal. This video streamer recounts spine-chilling tales of the horrors he encountered on the island. ▼ Puzzles New puzzle challenges have been added to your island explorations. ▼ Success Rate Control Unlock this feature by reaching any ending other than the Bad Ending. In scenes where dice-roll choices appear, a button will now appear in the bottom-left corner of the screen. Adjust the success rate to 0 for guaranteed failure or 100 for guaranteed success. Comes in handy for completing every scenario! ▼ Enhanced Effects New effects have been added throughout the game to better reflect the emotions and mental state of the characters. ▼ Other Improvements Design adjustments have been made to the title screen, window frames, and other visual elements for a more polished experience.Read full article on Community Announcements (Gotcha Gotcha Games)






